The rtypwidth() function

This sample program is in the rtypwidth.ec file in the demo directory.

/*
   * rtypwidth.ec *

   This program displays the name of each column in the 'orders' table and
   the number of characters required to store the column when the  
   data type is converted to characters.
*/

#include <stdio.h>

#define WARNNOTIFY      1
#define NOWARNNOTIFY    0

main(argc, argv)
int argc;
char *argv[];
{
    mint i, numchars;

    int4 exp_chk();
    char db_stmnt[50];
    struct sqlda *sql_desc;
    struct sqlvar_struct *col;

    EXEC SQL BEGIN DECLARE SECTION;
   char db_name[20];
    EXEC SQL END DECLARE SECTION;

    printf("RTYPWIDTH Sample ESQL Program running.\n\n");

    if (argc > 2)            /* correct no. of args? */
      {
      printf("\nUsage: %s [database]\nIncorrect no. of argument(s)\n",
      argv[0]);
      exit(1);
      }
   strcpy(db_name, "stores7");
    if (argc == 2)
      strcpy(db_name, argv[1]);

   EXEC SQL connect to :db_name;
   sprintf(db_stmnt, "CONNECT TO %s", argv[1]);
   exp_chk(db_stmnt, NOWARNNOTIFY);

   printf("Connected to %s\n", db_name);

    EXEC SQL prepare query_1 from 'select * from orders';  /* prepare select */
    if(exp_chk("Prepare", WARNNOTIFY) == 1)
      exit(1);
    EXEC SQL describe query_1 into sql_desc;            /* setup sqlda */
    if(exp_chk("Describe", WARNNOTIFY) == 1)
      exit(1);
    printf("\n\tColumn Name    \t# chars\n");

/*
     * For each column in orders print the column name and the minimum
     * number of characters required to convert the SQL type to a character
     * data type
     */
    for (i = 0, col = sql_desc->sqlvar; i < sql_desc->sqld; i++, col++)
      {
      numchars = rtypwidth(col->sqltype, col->sqllen);
      printf("\t%-15s\t%d\n", col->sqlname, numchars);
      }

    printf("\nRTYPWIDTH Sample Program over.\n\n");
}

/*
 *  The exp_chk() file contains the exception handling functions to
 *  check the SQLSTATE status variable to see if an error has occurred
 *  following an SQL statement. If a warning or an error has
 *  occurred, exp_chk() executes the GET DIAGNOSTICS statement and
 *  prints the detail for each exception that is returned.
 */
EXEC SQL include exp_chk.ec